Kidney stones in adults

Kidney stones – Definition

Kidney stones are pieces of a stone or crystal-like material in the urine. These stones form inside the kidneys or other parts of the urinary tract. The kidneys remove waste (in the form of urine) from the body. They also balance the water and electrolyte content in the blood by filtering salt and water.

There are several types of kidney stones:

The most common type has mostly calcium along with oxalate or phosphate.

Others types contain uric acid, struvite, and/or cystine.

Kidney stones – Causes

Some of the known causes include:

Chemotherapy (ie, uric acid stone)

Too much oxalate in urine (hyperoxaluria)

Too little magnesium in urine (hypomagnesemia)

Too much calcium in the urine (hypercalciuria)

Too much calcium in the blood (hypercalcemia)

Too little citrate in the urine (hypocitraturia)

Bacteria around which a stone can form

Too much uric acid in the urine (hyperuricuria, gout)

Bacteria that produce enzymes that increase the amount of ammonia and struvite in the urine

Kidney stones – Symptoms

Occasionally, kidney stones do not cause symptoms. They leave the body in the urine. The condition, though, can cause severe pain.

Symptoms include:

Sharp, stabbing pain in the mid-back that may occur every few minutes and last from 20 minutes to one hour

Pain in the lower abdomen and groin area, labia, or testicles

Nausea, vomiting, or diarrhea

Blood in the urine

Frequent urge to urinate

Burning pain during urination

Fever

Urinary tract infection

Kidney stones – Diagnosis

The doctor will ask about your symptoms and medical history. A physical exam will be done.

Tests may include:

Your doctor may order tests to gather information about your urine such as:

Urinalysis

24-hour urine

Urine culture

Blood tests

Your doctor may need detailed pictures of your kidneys and urinary system. These can be made with:

Spiral CT scan

Ultrasound

Intravenous pyelogram (IVP) (less commonly used today)

Kidney stones – Treatment

Treatment depends on the size and location of the kidney stone. Treatment may include:

Water

For small kidney stones, drinking at least two or three quarts of water a day helps the body pass the stone in the urine. The doctor may provide a special cup to catch the stone when it passes so it can be analyzed. If you are having a hard time keeping fluids down, you may need to be hospitalized to receive fluids in your vein.

Medications and Nerve Stimulation

Your doctor may recommend that you take pain medication. You may need medication that is given in the vein or in the muscles.